Text (4th/5th+errata): Whenever a player taps a land for mana, that player adds one mana to his or her mana pool of any type that land produced. [Oracle 2008/04/01]
This is a triggered mana ability. [D'Angelo 2000/03/03]
Mana Flare adds one of whatever color the land produces after applying any land type or color changing effects. [Duelist Magazine #6, Page 130]
When used with lands that produce multiple colors, such as Badlands, Mana Flare produces 2 of one color, not one of each. [bethmo 1994/05/12]
When used with Urza's lands (and other colorless producing lands) they produce one extra colorless mana each. [bethmo 1994/05/12]
Only produces extra mana when land is tapped for mana, not when tapped by Twiddle or for some other effect. [bethmo 1994/04/01]
Applies to all players in multiplayer games. [Duelist Magazine #4, Page 64]
If the land produces more than one color or type of mana at a single time, such as with Balduvian Trading Post, you choose which kind of mana the Mana Flare actually provides. [Duelist Magazine #12, Page 26]
Any restrictions on the mana generated by the land are copied along with the color. [bethmo 1996/12/07]
The mana is provided when the triggered ability resolves. [Duelist Magazine #18, Page 29]
